The body temperature of an individual has a significant effect upon the athletic performance of the individual when engaging in athletic activities. Components of the body temperature include core temperature and surface temperature, for example. Whereas the core temperature is associated with interior portions of the individual (i.e., the internal organs), the surface temperature is a measure of the temperature associated with the surface of the individual (i.e., the skin). Although the core temperature and surface temperature are discrete measurements and may vary significantly, the core temperature has an effect upon the surface temperature, and the surface temperature has a corresponding effect upon the core temperature.
As the individual begins engaging in an athletic activity, including either practice sessions or competitions, the core temperature of the individual may rise as the level of athletic activity increases, particularly in relatively hot or humid climates. Although a rise in core temperature is a normal aspect of engaging in athletic activities, the athletic performance of the individual begins to decrease once the core temperature increases above a threshold temperature that may vary for different individuals. For example, the speed of the individual when running, the height of the individual when jumping, the reaction time of the individual when responding to other athletes, and the overall strength of the individual may decrease as the core temperature increases beyond the threshold temperature. The threshold temperature at which athletic performance decreases may be approximately 39 degrees Celsius (i.e., 102 degrees Fahrenheit), but varies between different individuals. Accordingly, moderating or otherwise delaying a rise in the core temperature during an athletic activity has the potential to reduce heat stress and increase the overall athletic performance of the individual.